Driverless trains are becoming increasingly common, especially in urban transportation systems. Existing solutions depend on intelligent wayside controllers, such as Zone Controllers or a Vehicle Control Centre to track all trains, set and lock routes, and authorize train movements. Such solutions are described in IEEE 1474, which relates to Communications Based Train Control. An example of such a system is the Seltrac™ system manufactured by Thales.
These devices have an expensive project life cycle, are complex to design, install, certify and maintain, and need to be customized with the rules of the operating railway. Failure of a single wayside control device shuts down all automatic operation within the territory governed by that device, Additionally, these devices require access controlled equipment rooms, and these rooms can be expensive to build for this purpose.